netdata/netdata

// SPDX-License-Identifier: GPL-3.0-or-later

package selector

import (
    "github.com/netdata/netdata/go/go.d.plugin/pkg/matcher"

    "github.com/prometheus/prometheus/model/labels"
)

type Selector interface {
    Matches(lbs labels.Labels) bool
}

const (
    OpEqual             = "="
    OpNegEqual          = "!="
    OpRegexp            = "=~"
    OpNegRegexp         = "!~"
    OpSimplePatterns    = "=*"
    OpNegSimplePatterns = "!*"
)

type labelSelector struct {
    name string
    m    matcher.Matcher
}

func (s labelSelector) Matches(lbs labels.Labels) bool {
    if s.name == labels.MetricName {
        return s.m.MatchString(lbs[0].Value)
    }
    if label, ok := lookupLabel(s.name, lbs[1:]); ok {
        return s.m.MatchString(label.Value)
    }
    return false
}

type Func func(lbs labels.Labels) bool

func (fn Func) Matches(lbs labels.Labels) bool {
    return fn(lbs)
}

func lookupLabel(name string, lbs labels.Labels) (labels.Label, bool) {
    for _, label := range lbs {
        if label.Name == name {
            return label, true
        }
    }
    return labels.Label{}, false
}